Manufacture of aluminum-foil.



ALFRED GAUTSGHI, OF GONTENSGHWIL, SWITZERLAND.

MANUFACTURE OF ALUMINUM-FOIL.

Specification of Letters Patent;

Patented April 6, 1909.

Application filed February 27, 1906. Serial No. 808,287.

To all whom it may concern:

Be it known that I, ALFRED GAUTSCHI, manufacturer, a citizen of Switzerland, re-

siding at Gontenschwil, Canton of Argotie,

Switzerland, have invented new and "useful Improvements in or Relating to the Manufacture of Aluminum-Foil, of which the following is a specification.

Flexible aluminum foil, serving the same purposes as the tin foil generally employed for packing chocolate and other eatables, could not hitherto be obtained owing to the great diiiiculties presented in the rolling.

'It is true that ithas been found possible to roll aluminum in sheets of a thickness exceeding 1/10 of a millimeter, but not below this; the object in View was not thereby attained because the tin foil usually employed is far thinner than 1/10 of a millimeter.

Bv my process of manufacture, which is -hereinafter described, I have succeeded in obtaining in good condition sheets of pure aluminum of great flexibility and having the same thickness as the thinnest of tin 011.

The object of my invention is therefore a process of producing an aluminum foil having a thickness of less than 1/10 of a millimeter.

v The process is carried out in the following mannerz-Startirig with a sheet of pure aluminum of a certain area. approximately 1 mm. in thickness and perfectly annealed, a

. scribed above until the len has sheet sthen coated with the oil solution indifirst rolling of thin sheet is efiected by means of a rolling mill of any ap ro riate kind, until the sheet reaches aiiliic ess of about 3/10ths. of a, millimeter. The sheet is then folded in two upon itself and rolled until its length is doubled by means of a rolling mill the cylinders of which are perforated along their axes and are heated by a circulation of hot water to a tem eratun: of about 45 0., I

to facilitate the ro of the sheets. The sheet is then unfolded and its surface coated on one side with a solution of mineral oil (soluble in water) and water, this solution being, of suitable viscosit for example two artsof' oil to one part 0 water. The sheet is then again folded so that its coated faces are in cont-act and it is (passed through the rolling mill with heate cylinders as deh of the sheet again been doubled. no side of this.

cated above and it is folded on itself and am cordance with what is termed the packet rolled and so on in succession, in acsystem of rolling, carebeing taken that there is always present between the sheets in contact a slight layer of the oil solution. The oil used ma be glycerin, or any mineral or vegetable 0' may be used .-which is soluble in water. This solubility is obtained by means of a secret process which is not shown by me. The oil must be mixed with a greatdeal of water, because the sheets whichit is sought to obtain being extremely thin, it is necessary that the oily substances between each sheet be very slight in quantity and yet thoroughly spread everywhere, conditions which cannot be had with pure oil. This mixture of oil and water has for its purpose to prevent the sheets from sticking together when they are rolled out. When the proper thickness has been attained, the rollin is suspended and the block of sheets is placed in a furnace Where it is annealed. On leaving the furnace after being slowly cooled, the block of aluminum sheets is cut with a shears and the sheets are detached one from the other ready for use.

It will be noticed that no annealing of the sheets of. aluminum takes place from the time at which they are coated with the oily solution until the rolling operation is completed.

The aluminum foil thus obtained is exceedingly flexible and presents the, properties of being inoxidizable, unchangeab e and exceedingly light, which is not the case with tin foil. In addition, this aluminum foil does not impart to alimentary products faces of the sheets in contact one with the other being always coated with a'solution of oil and water, the rolling being 'eifected between heated cylinders.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

p ALF. GAUTSOHL.

Witnesses:

Josnrn Smon, A. Lmnnnxnnon'r.

a the peculiar taste that is always imparted to 

